Electrical connectors of the type described above are used, for example, in the automotive industry. The contact elements of the mating connector may be either contact pads or female elements such as bushings, which are engaged by the pins. The air-tight chamber prevents intrusion of moisture which could degrade the contact surfaces. In order to obtain an air-tight chamber when the electrical connector and its mating connector are engaged with one another, there can be an integrated sealing system or a separate seal made from EPDM (Ethylene Propylene Diene Monomer) rubber and the like between the electrical connector and its mating connector.
The inventors of the present invention have recognized that even the residual moisture within the connector can cause degradation of the contacts, in particular when there are silver contacts, and that the reason for this is electrical “silver migration” which may occur on silver contacts which are exposed to moisture, even when its quantity is very small.
WO 2007/036369 A1 discloses to use within vehicle electrical systems a moisture absorbing material, for example water absorbing polymers, which are polymers that can absorb and retain extremely large amounts of liquids relative to their own mass. Suitable polymers would be polyacrylate, for example acrylic acid which is neutralized by sodium. The moisture absorbing material has to be applied on single wires and feedthroughs during the assembly of the vehicle electrical systems. If a workman would forget such a treatment, moisture protection would be insufficient.
The object of the present invention is to provide an electrical connector of the above mentioned type which would reliably prevent silver migration without any additional mounting steps.